Re the first proposal, to incorporate the hostname somewhere. This
would be cleanest put into the URL itself :-
GET http://hostname/fred http/2.0
This is the syntax for proxy redirects.
This suggestion conflicts with the aims of the second I'm affraid. I
don't think that its a good thing for a server to not know its name.
Proxying is far too prevelant now and a server that doth not know
its name shall be called a LOOP.
Phill